Railway brake control mechanism



Nov. 1a, 1952 F. S. SWICKARD RAILWAY BRAKE CONTROL. MECHANISM Filed prill0, 1945 5 Sheets-Sheet l 2M [Lrg/QM bd W Nov. 18, 1952 Filed April lO,1945 F. S. SWICKARD RAILWAY BRAKE CONTROL MECHANISM A3 Sheets-Sheet 233% wodka/k (AJ.- @5MM/of www N0V 18, 1952 F. s. swlcKARD 2,618,514

RAILWAY BRAKE CONTROL MECHANISM Filed April 10, 1945 5 Sheets-Sheet 3/fwsRw/l mummy Patented Nov. 18, 1952 2,6l8,5li

RALWAY BRAKE CONTROL MECHANISM Frank S. Swickard, Denver, Colo.; LauraJanette Swickard, administratrix of said Frank S.

Swickard, deceased Application April 10, 1945, Serial No. 587,533

(Cl. 3dB-l5) 22 Claims.

This invention relates to air brakes for multiple unit trains such asrailway trains.

ln operating automatic air brakes on trains with the usual constructionand particularly when a train is very long, as a freight train,considerable time is lost in applying the brakes to the rear cars afterthe brake valve is placed in service position on the locomotive. Thistime loss is due to the fact that the triple valve of each car, whichcontrols the brake operation on its car, is dependent for its operationon the drop in pressure in the brake pipe, brought about by aregistration of the brake pipe with the atmosphere through the brakevalve in service position. As the friction of the air on the inside ofthe brake pipe retards the flow of air therethrough, it is obvious thatthe opening of a port from the brake valve to the atmosphere, on thelocomotive will cause successive operation of the several triple valvesin order from front to rear E as the friction of the air is retarded, onits way to the exhaust through the brake valve. And since, due tofriction, it takes some time to bring about a sufficient pressure dropin the train line to thereby bring about a successive operation of thebrake mechanisms from front to rear, it follows that with the usualconstructions, the brake applications are not simultaneous.

In addition to the loss of time, there is a loss of pressure in thebrake line which drop in the usual construction is necessary to operatethe triple valve to open the connection from the reservoir to the brakecylinder. This loss of pressure has to be regained as well as thepressure loss due to the actual brake operation.

The primary object of this invention is the provision of an improvementin air brakes for vehicle trains as railroad trains.

Another object of the invention is the provision of an improved brakemechanism wherein the pressure Within the train line or brake pipe ismaintained while the application of the brakes is made.

Another object of the invention is the provision of an improved brakemechanism wherein all brake applications and releases may be performedindependently of the brake valve.

Another object of the invention is the provision oi an improved brakemechanism wherein all oi the brake applications throughout the train maybe made simultaneously.

Still another object of the invention is the provision of an improvedbrake mechanism wherein all of the brake applications and releases areperformed throughout the train and are made simultaneously.

A still further object of the invention is the provision of an improvedbrake mechanism wherein, regardless of the piston travel, the pressureson the several brake pistons will be maintained substantially the samethroughout, during variable pressure changes.

A further object of the invention is the provision of an improved brakemechanism wherein the brake cylinder pressure in the several brakecylinders of the train units is the same and may be indicated in theengine cab or at any other place on any unit or on all units of thetrain.

A still further object of the invention is the provision of an improvedbrake mechanism wherein the brake piston pressure in the several brakecylinders of the train units may be variably controlled from the enginecab or from any one or more units of the train While still maintainingequal brake piston pressure throughout the units of the train.

A still further object of the invention is the provision of an improvedbrake mechanism wherein the brake cylinder pressure can be increasedfrom a rear point on the train, as for example from the Caboose, and bemade simultaneously in all parts of the train.

A still further object of the invention is the provision of an improvedbrake mechanism wherein the brake piston pressures of the several brakecylinders are made to change simultaneously and together throughout thetrain.

Another and still further object of the invention is the provision of animproved brake mechanism wherein the brake piston pressures of theseveral cylinders may be controlled without rst lowering the pressure inthe brake pipe.

Still another and further object of the invention is the provision of animproved brake mechanism wherein the pressures from the reservoirs maybe used for the brake cylinders without rst lowering the pressure of thebrake pipe.

Still another and further object of the invention is the provision of animproved brake mechanism wherein the brake piston pressures are appliedfrom the reservoirs simultaneously and are substantially equal duringranges.

Still anotlie" and further object oi the invention the provision of animproved brake mechanism wherein the brake cylinder pressures may eeapplied and released independently of any changes in the brake pipepressure.

Still another and further object oi the invention is the provision of animproved brake mechanism wherein when, for any reason the brake 3 pipebecomes broken, my improved structure can be set for brake action and inwhich case, the brake piston pressures may be maintained and the brakesmaintained in se-t position while the reservoirs are recharged tostandard pressure.

Other and further objects will be apparent to those skilled in the artfrom a reading of the complete specication.

Referring to the drawing wherein I have illustrated an embodiment of theinvention:

Fig. 1 is a cross section of the triple valve of a railway car brakemechanism showing the invention attached thereto in running position.

Fig. 2 is a cross section of the invention showing working parts inprimary service position with the parts slightly enlarged for clearness.

Fig. 3 is a View similar to Fig. 2 but with parts in position after thepredetermined pressure in the brake cylinder has been attained, with thegraduating valve closed.

Fig. 4 is a View similar to Fig. 3 with the parts in positionsimmediately after applying higher pressure to the brake cylinder.

Fig. 5 is a view similar to Fig. 4 showing the parts in position afterthe increased predetermined cylinder pressure has been reached and withthe graduating valve closed.

Fig. 6 is a cross section on the line '6-6 of Fig. 1.

Fig. 'I is a cross section on the line of Fig. 2.

Fig. 8 is a cross section on the line 8 3 of Fig. 3.

Fig. 9 is a fragmental diagrammatic showing of a slightly diierentconnection of the invention to the conventional mechanism shown in Fig.l.

Similar yreference characters refer to the same or similar partsthroughout the specification and drawing.

In the drawing, 20 designates the brake pipe which extends from thelocomotive or other front unit of the train to the rear unit thereof'.

In the usualv construction of brake mechanism, a brake valve whichcontrols the application of the brakes, opens the brake pipe toatmosphere either slowly to produce a service or light application ofthe brakes, or suddenly to reduce the airpressure in the brake pipe,thus bringing about an emergency application of the brakes. The brakevalve also controls the admission of air from the power operated aircompressor on the locomotive through the brake valve and itsconnections, through the brake pipe to replenish the air pressure inthebrake pipe and the reservoir for purposes to be presently described.Various other auxiliary apparatus is supplied to assist in the operationof the compressor and brake valve such as the equalizing reservoir, thefeed Valve andthe pump governor, all of which are well known to thoseskilled in the art. For this reason, they will not be further describedor illustrated.

In order to control the air pressure on each of the several units of thetrain, there is provided a triple valve the housing of which I havedesignated generally by the reference character 2|. rlhis housing 2| isconnected to the brake pipe 20 by means of a pipe 23 with a cut-off 22.

The pipe 23 is connected to a passage 25 in the triple valve housing 2|which connects to a chamber 26. Within a plug 272, screwed in the end ofthe housing 2|, is an opening in which slides a, spindle 2'1 whichcarries the resistor spring 28. The head 2lb is adjacent the chamber 23which is provided with a leather gasket 29a.

The interior of the chamber 29 is cylindrical and provides an operatingsurface for the triple valve piston 30. The triple valve piston 30 isprovided with a stem 3|)a which extends into the slide valve chamber 3I. On one side of the slide valve chamber 3| as at the bottom, as shown,is a slide valve seat 3|a upon which is seated the slide valve 32. Thisslide valve 32 is provided inV its bottom with a groove or chamber 32a.

Extending from the chamber 3| is a, pipe 33 which connects to theauxiliary reservoir 34, which latter serves as a supply for the airpressure.

Connected through the valve seat 3 |a is a passage 3|b, 'which' isconnected to a pipe 35 leading to the brake cylinder 36 in whichoperates the brake piston 31. Extending also from the valve seat 3|, isa passage 3|c which in the normal construction is open to the atmospherebut in the present case with this invention attached, is connected tothe passage If, to be later vdescribed. A 'i The triple valve slidevalve 32. has its groove or chamber 32|,ab in place over the passagesv'3|b and 3|?, so arranged'thatfin one position, the slide valve chamber3,2,afwill bridge and, connect the openings 3|b andv 3|c and in anotherposition, will preventthe passage oyfair, beftvv/een` these twopassages.

The stem 3G? of the triple valve piston, is provided with anoverhanging'v portion 3,319, termed the piston stem end. Secured to thepiston stem tov move longitudinally therewith, is a lgraduating valve 33 whichV has a cylindrical portion which moves in av correspondinglyshaped cylinder withinthe slide valve'32.

An opening'Sl!b in the slide valve 32 is connected'witha passage 32cwhich terminates in a, position to register with the passage 3 IP whenthe projection 30d movesto a position adjacent tothe head 21a in aposition where `further movement would co'mpress'the spring'ZS. At apoint in the passage 32e near. th'e opening 32D is the valve'seat v32dupon which the conical end ofthe graduating `valve38` in. one position,reststo close the connection between the opening 32band the passage 32cmOn the stem 30d is a shoulder 30e which with the stem end, 30h,"permitsma limited, relative movement between the stem 30d. and theAslide valve so.

It will be noted that when the. piston 30. is in position, so that thechamber 23 hasitsgreatest capacity, there is a,r small passage 3,9.around the piston 3|)v toconnect the chambersfZS and 3| to permit thepassage of air under pressure from the brake pipe 20 to pass by way ofthe pipe 23, the passage 25 the chamber 26, the chamber 29, the smallpassage 39;, the chamber 3| through the pipe 33,to the auxiliaryreservoir 3 4. Y

With the piston 30 inthe positionA just described, the air pressure fromthe brake line 20 will soon ll the auxiliary reservoir 34 to the samepressure as the brake pipe. As thelbrake cylinder 36 is connectedythrough the pipe 3,5 the passage 3|b, the groove or. chamber 32a and thepassage 3|c.throug`h the passage 00d to atmosphere, as will be laterdescribed, the spring 31a will force the rod 3.'|b tobe retracted tomove the brakes to running position. A gage 36a is provided withconnection tothe brake cylinder and may be applied to the locomotiveandf any and allbrake cylinders.

It being understood thaty in the usual brake construction, the passage3|c is always open to atmosphere and with this in mind, the partsheretofore described in detail are old and well known in the art.

However, in order to fully understand this invention, the serviceapplication and emergency applications of the above well-known brakemechanisms will be described.

With the parts in the running positions as just described, air is slowlypermitted to escape from the brake pipe. This permits a pressurereduction in the chamber 23 by way of the pipe 23, the passage 25 andthe chamber 2S, to the chamber 29. With the higher pressure in thechamber 3! and the reduced pressure, in the chamber 23, the piston 33moves away from the chamber 3l. The rst part of this movement causes thepiston 3i) to cover the small passage 39. The first part of thismovement of the piston 3l withdraws the graduating valve 38 from itsseat 32d and permits the air pressure from the auxiliary reservoir 34and the chamber 3I to enter the opening 32h and pass to the passage 32C.It will be noted at this point in the operation that due to the slightrelative movement, already described, which is possible between the stemend 32h `and the slide valve 32, the rst part of the movement of thepiston 33 will move the graduating valve 33 and the stem 30a but theslide valve 32 will not move until the stem end 30h engages the slidevalve 32.

As the piston 3I moves farther from the chamber 3l, the slide valvemoves in the same direction with the piston. The rst result of thisfurther movement permits the chamber 32a to be moved so that it nolonger connects the passages 3 I b and 3 Ic, the passage 3 Ib, beingblanked. But since the passage 3Ic is, in the usual construction,connected to atmosphere, it follows that the atmospheric connection isbroken to the brake cylinder 33.

The piston 3@ continues its movement, moving the slide valve 32 with it,until the passage 32o is opened to the passage 31h. But since, asalready stated, the pressure of the auxiliary reservoir is in thepassage 32e, this opening of the latter immediately permits the pressurefrom the reservoir 34 to enter the brake cylinder 35 and press the rod31D against its spring 31a to apply the brakes. It is to be here notedthat, in the usual construction, due to the variation in brake pistontravel according to the setting of the brakes, and the time of operationof the triple valve in applying the brakes, there will be a variation inthe brake cylinder pressure and consequently a variation in the actualbrake pressure at the wheels. And since with the present invention, thedetails of which will be later described, the pressure is predeterminedand regulated from the brake cylinder itself, the brake cylinderpressure with this invention is .at any one time, the same throughoutthe train.

When the brakes, with the usual construction, have given the properbraking action, the brake valve is closed. This action stops the passageof air from the brake pipe to the atmosphere and consequently stops themovement of the piston 33, with the pressure equal on both of its sides.But since the pressure within the chambers 3| will continue to decreasedue to the continued passage of air from the auxiliary reservoir 33 andthe chamber 3l to the brake cylinder 33, there will be a reduction inpressure in the chamber 3|, which will cause a slight movement of thepiston 30 back toward the cylinder 3 I. While this movement is notgreat, it is sufficient to 6 move the graduating valve 32 to its conicalseat 32d, thereby shutting off the air connection from the opening 32hto the passage 32e. This position of the graduating valve 38 is calledthe lap position and the pressure in the brake cylinder is retained.

When, however, the brake pipe is again connected to the normal highpressure, the piston 3i] is moved toward the chamber 3l. This movementkeeps the valve 38 on its seat 32d, maintaining closed the connectionbetween the auxiliary reservoir and the brake cylinder and an instantlater moves the slide valve 32 so that the groove or chamber 32a willconnect the pressure side of the brake piston 3l', in the usualconstruction, to atmosphere. This permits the retracting spring 31a towithdraw the brake rod 31h and its brake.

But as the piston 33 moves to its limit of position toward the chamber 3I, which is the charging position, the small passage 33 is opened andthe pressure in the auxiliary reservoir is restored to its normalpressure of the brake pipe.

If it is desired to give the train a sudden stop, it is only necessaryto set the brake valve to permit the air in the brake pipe to besuddenly released to atmosphere. This causes the air pressure within thechamber 2Q to be quickly reduced below that of the chamber 3l and thereservoir 35i. The piston 33 at once moves until the projection 33dengages the head 2lb and compresses the spring Z8 until the bead 33e issealed against the gasket Eea. This action moves the slide valve i2 withthe piston stem and places the slide valve 32 so that its end 32e is `tothe leftbeyond the opening of the pass-age Sib, thus admitting the fullpressure of the chamber 3l directly to the piston chamber 33. Thisoperates the brake piston at the equalized pressure between thereservoir and the brake cylinder. This same action takes place when anaccidental break in the brake pipe occurs.

The operation of returning to running position has already beendescribed.

The construction of my improved brake control mechanism will now bedescribed.

A main body it@ is illustrated as cylindrical in form and is providedwith a bushing IUI having a chamber iIa which has, as illustrated, onits bottom, a stationary valve seat I0 I b in the bottom of vthe chamberI tia. This valve seat IIlIb is preferably in a plane.

The body member It@ is provided with an opening Itib which registerswith an opening IDIc in the bushing IiI to provide a connection from thechamber its@ through a boss Ic which latter is connected to the carauxiliary reservoir 3:5 already described, by a pipe IZ.

The body member loi! land the stationary valve seat bushing Ii areprovided with respective registering openings Iiiild and Ild. Theopening Iiid passes through a boss I 30e which is connected to the carbrake cylinder through the triple valve exhaust by the tube |03. Thevalve seat bushing ISI is provided with an opening it Ie which connectsat its outer end to a passage Milf in the body member IEW.. This passageIOf extends around the outside of the bushing IUI as a groove in thebody it@ to an opening i633 through a boss its where it is connected toatmosphere to permit the exhausting of the brake cylinder to theatmosphere. It is to be observed that when my invention is connected toany of .the usual constructions, the connection of the brake cylinder 35to the atmosphere can be made only when the valve |05, to be presentlydescribed, permits such connection.

On the valve seat I Ib is a slide valve |05 which is provided with anopening Ia. This opening |05a, in one position registers with theopening |0Id already described. The slide valve |05 is provided with asurface I 05h which registers with the surface I5 I b.

To one side of the opening |05a is a slot |050 which is of suiicientlength and in position to span and connect .the openings IOId and I0|ein the valve seat bushing IOI, when the valve |05 is moved in onedirection.

Suitably secured to the end of the body member |00 is the magnethousing. |06, in the form of a cylinder, one end of which is against theend of the body member |00, the o-ther end beineT closed by the endmember IIll. The end member |01 and the housing |06 are held in place bya set of stud bolts |08 which are threaded into the body member |00.

The slide valve |05 is provided with an end lug I 05d into which isscrewed a stud bolt |09. A spacer collar IIO holds the magnet armature III spaced from the lug |05d, the collar IIO and the armature I I I beingheld in place by the stud |09.

On the inner side of the end member It'I is a projecting spring guideI0'la'to hold in place the compression spring IIZa, which is heldbetween the end member |07 and movable magnet armature I I I.

A suitable electro-magnet |I2 is provided in position to attract itsarmature I I I and move the parts III, IIEI, |05 and the valve |05 whenthe electro-magnet I I2 is energized. When energized the magnet |I2moves its armature III and the valve I .5,to.such a position that theopening I 55a registers with the opening IOId of the bushing I. Inreleased position, the spring |I2a forces the valve |05 Ito a positionWhere the groove or slot |1550 registers with and connects the openingsI|d and IElIe in the bushing IOI, thus connecting the interior of thebrake cylinder through passage Id 'to the opening |00f through the bossL04, to atmosphere, whenever the triple valve is in running position.

Opposite the` housing ite and attached tothe mainl body |50; is ahousing IIS secured in place With-` an endpiecel IM by the studs I I5which are threaded into thebody |00.

Within thehousing ||3 isa cylindrical surface IISa in which is slidablymounted a piston IIS. This piston. I I5. with its expansible chamber I|31) forms what I term a pressure regulating pneumatic. Between the mainbody member |00 and the housing I|3 is a separating partition I Il whichhas an opening at its center. Through this central opening passes apiston rod I I8 which is secured to a graduating valve I2 I. This valve|2I is provided with an opening I 2| a which inI one position registerswith -the opening |05a of the slidevalvel I05Yand in another position isout oi such registration.

The` graduating valve I2I is provided with bosses vI 2 Io which haveopenings to receive spring pressed pliingers` |22, the heads of whichengage the wall ofthe chamber Iota, reacting to force the valve I2Iagainst the slide valve |05, and the latter, in turn, against the valveseat I 0| b.

The piston I|6 is provided with a spring guide IIBzin which is anopening I |61) within which is located a spring |23a Whose opposite endengagesthe boss I Ida, A second spring |2317 is outsdethe guide IIIa'andis of-suiii-cient length to reachv fromthev extendedA position of theadjacent wall of the piston I I B to the adjacent shoulder I 24a of themagnet armature I 24. This armature |24 is attracted to and is moved bythe electro-magnet |25 when the latter is energized. This armature |24is free to move longitudinally in the chamber of the housing I I3. Itwill be apparent that when the electro-magnet |25 is energized, thearmature |24 will cause the compression of the spring I23b for a purposeto be described. The end piece H4 is provided with a boss Illia which isprovided with a vent |I4b. This vent maintains the outer space |I3c ofthe housing I I3 at atmospheric pressure.

I Will now describe the operation of my invention, it being borne inmind that, as illustrated,

the three outside operative connections are (l) through the passage|0027 to the pressure reservoir 34 of the car, (2) to the atmospherethrough the passage |03 and (3) to the brake cylinder 36 through thepassage |0001. Although noi-l necessarily so, in the present illustratedform, the pas sage Iilild is connected to the brake cylinder through theexhaust connection of the triple valve of the usual automatic brakemechanism. It is to be here noted that since the exhaust from the triplevalve is through my improved structure, to the atmosphere, no release ofpressure in the brake cylinder can be brought about unless theatmospheric connection of my improved structure is open to theatmosphere.

Assuming the parts to be in running position, brakes not applied, theelectro-magnets II2 and |25 not energized, the slide valve |05,graduating valve I 2| and other parts will be in running position asillustrated in Fig. l. It will be noted that the piston I I 5, underinfluence of the spring I23a will hold the valve IZI with its openingI2|a in position to function, the opening I2Ie, being, however, blankedout from functioning by the slide valve |55, as illustrated in Fig. l.It is now-desired to apply a predetermined brake cylinder pressure of 5pounds per square inch.

In the engine cab, or wherever it is desired to have it located, theswitch handle 54 with its arcuate contacting arm Sd, is pivotallymounted on the contact plate 55. This arm a is normally out of contactwith the contact points 96 and Sl which connect, respectively, withthewires 98 and 55 leading to the respective electro-magnets ||2 and |25.On movement of the switch handle 94 so that Contact is made to the point56, the electro-magnet II2 is energized. This draws the armature I |I tothe left as illustrated in Fig. l.

The armature III through the operating rod |09, moves the slide valve|05 and blanks the connection between atmosphere and the brake cylinderthrough the passage II5cl and-immediately thereafter, opens theconnection from the chamber Ita through the opening I 65a to the brakecylinder by Way of the passage IIlId, Id. This is brought about by thefact that the chamber Ila is always connected directly to the pressuresupply through passage |0019. Pressure is thus applied to the brakecylinder.

But as soon as the slide valve I 05.0pens the pressure to the brakecylinder, it also applies pressure from the passage |0011, through thebypassage I 00g to the chamber II3b between the piston IIS and the WallIIL-|20. The spring I23a presses against the piston IIB at a strengththat when opposed by an air pressure'of 5 pounds per square inch withinthe chamber II3b, the pistonI I6 will move the graduating valve |2I'toclose communication from the chamber lla to the brake cylinder. It isbelieved obvious that the substitution of a spring |23@ of greaterstrength will give a greater predetermined pressure than pounds persquare inch within the chamber Mtb. The parts are now, as illustrated inFig. 3, in position to have produced and to maintain a pressure withinthe brake cylinder of 5 pounds per square inch. This pressure will bemaintained in the brake cylinder until released. Any leakage from thebrake cylinder is at once overcome by the opening of the graduatingvalve |2| to again raise the pressure to the predetermined 5 pounds persquare inch.

If it is desired to return the parts to running position, it isnecessary only to move the switch handle 94 counterclockwise, todisconnect the arm @im from the contact point 96. This causes thede-energization of the electro-magnet ||2. The spring ||2a then forcesthe armature to the right as illustrated with a consequent blanking outof the pressure connection through the opening i2 la by movement of thevalve m5, further movement of the valve |05, connecting the brakecylinder 3E to atmosphere through the cavity |5d in the slide valve |05.

If, however, instead of releasing the pressure to return the brakes torunning position, it is desired to go into a maximum braking position,

it is only necessary to move the handle 94 farther to the right so as toapply the electric power from the source of electric current 95a. Thisconnects the handle arm 94a to the contact point Sl leaving the armstill in contact with the contact point 95. This action energizes theWire S9 with the consequent energization of the electro-magnet It is tobe here noted that with my device in maximum braking position it ispossible to obtain a greater pressure than with the usual constructionin emergency position. This is for the reason that during the emergencyoperation of the invention, no drop in the pressure of the brake line ismade. Further, since the brake cylinder pressure through the duct lllllgcauses a uniform pressure throughout the train, less expenditure of airpressure is made for both the service and emergency applications. As thepresn ent invention is operated in maximum braking position, thepressure of the brake cylinder is supplied directly without reductionfrom the auxiliary reservoir. But the triple valve of the usualpneumatic brake mechanism being, for example, in running position; isconnected to the train line brake pipe and also to the auxiliaryreservoir. For this reason, when the auxiliary reservoir pressure beginsto fall, because of the passage of air therefrom to the brake cylinder,the pressure from the main line brake pipe will, at once pass throughthe triple valve to the auxiliary valve to build up the pressuretherein. This pressure at once builds up the brake cylinder pressureuntil the pressure is the same in the brake cylinder, the auxiliaryreservoir and the brake line.

The energization of the electro-magnet E draws the armature 12d to theleft as illustrated. The spring EQ2-2a is fully compressed, but themagnetization of the armature |251 compresses the second spring lih. Thespring iZb assisted by the expansive force of the spring |23a, moves thepiston l l5 to the left as shown in Fig. fi. This action opens theconnection between the chamber ila and the brake cylinder passage wildthrough the passage lila in a position somewhat l0 as this valve isshown in Fig. 4;. But this greater pressure passes through the passagelllg to the chamber llb, again moving the piston il@ and the valve l2!to the right to again close the Valve opening |2|a and shut oi thepressure supply from the chamber ltia.

While the pressure in the brake cylinder was mentioned as predeterminedto be 5 pounds per square inch with the electro-magnet H2 energized andthe electro-magnet |25 not energized, the last operation described withboth electro-magnets H2 and |25 energized, causes a compression of bothsprings |2311 and Vlb with a resultant increased predetermined pressurein the brake cylinder as for example with springs cf known compressionstrength, a pressure as high as pounds per square inch might be attainedwith a reservoir pressure of pounds per square inch.

As soon as the brakes begin to take effect and to avoid flat wheelscaused by locking of the same, the handle Sii may be returned to ruimingposition a sufficient length of time for the pressure in the brakecylinder to become reduced to the desired point. This pressure is mademanifest by the pressure control gage Sta in the engine cao.

The handle Sii is then returned to service brake position with the armSilla in contact with the contact point s6.

rEhe operation of the several parts which takes place when the switchhandle gli is moved to the left, will now be described. As soon as thehandle 55| is moved to break the contact with the Contact points Q5 and97, the electro-magnets H2 and |25 are de-energized. This deenergisationpermits the armatures and |2il to be forced, by their springs i |2115and |2313 away from the respective magnets H2 and |25. The rst result ofthis action is the movement of the slide valve its to cause the groovei850 to connect the opening lilla to the passage if. But since thepassage Mild is connected to the brake cylinder through the passage lildand the passage |3531* is connected to atmosphere, it follows that thebrake cylinder will, at ence be connected to atniosphere.

At the same time, the reduction in pressure within the brake cylinderalso permits the air pressure within the chamber H3?) to escape throughthe passage Iiig. The springs |23a and |2311 at once expand and thespring |23@ forces the piston H6 to be moved to the left as shown.

In the engine cab is the pressure gage 35a in full communication withthe brake cylinder oi the engine at all times. And since the pressure ofthe reservoirs of the engine and train are supplied at the same pressurefrom and by the same source and since the lowering of the pressure inall of the brake cylinders takes place simultaneously, it follows thatthe gage in the engine cab connected to the brake cylinder will indicatethe pressure of the many brake cylinders throughout the train as thechanges take place. In this way, the brake pressures will be the samethroughout the train, regardless of piston travel.

When it is observed in the cab that the pressure of the brake cylindershas dropped to the desired pressure as for example 50 pounds per squareinch, the switch handle 9d is moved to fcause the arm Qlito makeconnection or its arm sda with the contact point 95.

This service brake connection, as has been described, causes theenergization of the electrornagnet H2. This moves the armature iii andthe valve to the left as shown and blanks the connection between thebrake cylinder and the atmosphere through the passage |650 of the valve|85. At the same time, this causes registration of the passage ||i5a andthe passage Illd. If now, the pressure in the chamber ||3b is reducedto, for example as suggested, 5) pounds per square inch, it follows thatthe brake cylinder pressure Within the chamber ||3b will, through thepiston I I6, hold the graduating valve so that its opening |2|a will notregister with the passage lld through the slide valve opening |5a. Thiscondition is due to the fact that the spring |23a is set to open theopening Hlmy to the slide valve opening Ia, when and only when thepressure in the chamber H322 is less than 5 pounds per square inch.

With the parts in the positions as just described, the pressure of thereservoir 34 within the chamber Ila cannot reach the brake cylinderpassage Id because the brake cylinder pressure holds the opening |2|a ofthe graduating valve |2| off the opening |G5a. See Fig. 6. Thus noincrease in the brake cylinder pressure can take place. A furtherreduction in pressure within the brake cylinder may be made by againreturning the switch handle 94 to running position and again putting itin service brake position.

If now, an increase in the brake cylinder is desired, the switch handle94 is moved to place its arm 94a so as to contact the contact point 91.Immediately the magnet is energized, the armature |24 is drawn to itwith the resultant compression of the spring |231). This causes thepiston HS to overcome the pressure within the chamber ||3b and thepiston ||6 moves the graduating valve |2| to open the valve opening |2|ato complete the connection from the chamber lilla through the openings|85a, ld to the brake cylinder. The pressure then rises until it;reaches a maximum for the spring |231) or until the switch handle 94 ismoved to disconnect its arm 94a from the contact point 97, withresultant de-energization of the electro-magnet |25 and the weakening ofthe effective push of the spring |23b.

One important operation of my invention is performed in the case of abreak in the train line or brake pipe. This may occur in case of a traincoupler connection with a consequent separation of a portion of the carsfrom the remainder. Or it may occur simply by a break some where in thetrain line or brake pipe. In either case, the emergency brake settingtakes place and the train comes to a stop. In the usual course ofrestarting the train, the train line or brake pipe is again connectedand in the case of a separation of a portion of a train from the mainportion, it is necessary to raise the pressure in the train line orbrake pipe to recharge the reservoirs on the several cars. But in sodoing, it is necessary to release the triple valve and this release ofthe triple valve will, if the train is on a suffcient grade, permit thetrain to run away. With my construction this may be made impossible.

In considering this operation let us assume the brakes to be still setin emergency position, with the air and other connections restored.Instead of, at once applying high pressure to the train line or brakepipe, the handle 94 s moved to service brake position. This at oncemoves the armature and the slide Valve |05 to the left, blanking thepassages ld and lld from atmosphere due to the fact that the groove|El5c has been moved so that it cuts off the connection between thepassages |0|d and lle. This permits holding of the brake cylinderpressure until by the usual construction, the reservoir is recharged..

In Fig. 9 where a slight modification is illustrated, the connectionmild, |933: from the eX- haust passage 3|c of the usual construction hasa by-pass connection 20D to the pipe 35 which leads from the passage 3|bto the brake cylinder 36. In the by-pass connection '200 I place a checkvalve 20| which will permit one-way passage of air from the passage|0007., lil-"3x through the connection 20D to the brake cylinder. Thedischarge of air from the brake cylinder 36 is as already described. Bythis construction, air pressure can be applied or additional airpressure can be admitted, regardless of the position of the piston 30.

It is to be understood that the term reservoir is used to refer to anysufficient source of pressure for the operation of the brake piston inthe brake cylinder, that this pressure may be from any source as forexamples, the main reservoir which may be on the locomotive, anauxiliary reservoir which may be on a car or a reserve reservoir whichmay be at any convenient place to deliver its pressure; and that theparticular type of triple valve and other constructions of the standardrailroad equipment which has been illustrated and the particular form ofconstruction for applicants invention as illustrated are merelyillustrative and that the invention may be used in other relations or byitself without departing from the spirit of the invention and within itsscope as claimed.

Having described the invention, what I claim 1s:

1. In a railway brake mechanism having an air reservoir and brakecylinder on a car, a valve controlling a passage from the reservoir tothe brake cylinder, electro-magnetically operated means for operatingthe valve to place the brake cylinder under pressure, a second valveadjacent to and coacting with the first valve to control said passage,pneumatic means for operating the second valve to close the latter at apredetermined pressure in the brake cylinder and an electro-magneticdevice for opening the second valve to increase the pressure above thepredetermined brake cylinder pressure.

2. In a railway brake mechanism having an air reservoir and brakecylinder on a car, a valve, electro-magnetically operated means foroperating the valve to give the brake cylinder a predetermined pressure,a second valve coacting with the rst valve, pneumatic means foroperating the second valve to close the latter at the predeterminedpressure in the brake cylinder and a resilient electro-magneticallyoperated means for opening the second valve to increase the pressure toa higher pressure, the valves by controlling their electromagnetic meansbeing manually controllable to provide any desired pressure between therst named predetermined pressure and the higher pressure.

3. In a railway brake mechanism having an air reservoir and brakecylinder on a car, a valve having a port, electro-magnetically Operatedmeans for operating the valve to a fluid supply position, a second valvecoacting with and in movable contact with the first valve and having aport registrable with the first-named port to control passage of air tothe brake cylinder, Pneumatic means for operating the second valve underiniiuence of the brake cylinder pressure to move the second valve to aclosed-port position when the brake cylinder attains a predeterminedpressure, and operator-controlled power means including a resilientmember, independent of the first valve and in position to move thesecond valve to, at will, alter the relative positions of the ports andthereby vary the predetermined pressure.

fi. In a railway brake mechanism having an air reservoir and brakecylinder on a car, a valve, electro-magnetically operated means foroperating the valve to give the brake cylinder a predetermined pressure,a second valve coasting with the rst valve to control the passage of airto the brake cylinder, pneumatic means or operating the second valveunder influence of the brake cylinder pressure to move the second valveto closed position when the brake cylinder is at a second higherpredetermined pressure, and an electro-magnetic device for opening thesecond valve to increase the pressure in the brake cylinder above thepredetermined pressure the firstnamed valve and its electro-magneticallyoperated means having connections to variably control, at will, thebrake pressure at any point between the predetermined pressures.

5. In a railway brake mechanism having an air reservoir and a brakecylinder on a car, a valve, electro-magnetically operated means foroperating the valve, a second valve, means in the first valve forconnecting the brake cylinder with the atmosphere, registrable openingsin each of the valves for effecting a pressure supply connection to thebrake cylinder from the air reservoir when the two openings are inregistration, pneumatically operated means connected to the brakecylinder for moving the second valve to disestablish said connectionwhen the air in the 4lorake cylinder attains a predetermined pressure,an operator-controlled electro-magnetic power device including aresilient connection, in a position to exert a force to move the secondvalve to :ce-establish said connection, thus increasing saidpredetermined pressure.

6. In a railway brake mechanism having an reservoir and brake cylinderon a car, a valve, electro-magnetically operated means for operating thevalve, a second valve, means in the first valve for connecting the brakecylinder with atmosphere, registering openings in each of the valves formaking a pressure connection to the brake cyiinder when the two openingsare in registration, pneumaticaliy operated means for moving the secondvalve to closed position when the air in the brake cylinder is at thepredetermined pressure and an electro-magnetic device for counteractingthe pneumatically operated means for increasing the pressure of thebrake cylinder above the predetermined pressure.

7. In a railway brake mechanism having an air reservoir and brakecyiinder on a car, a valve, electro-magnetically operated means foroperating the valve, a second valve, means in the first valve forconnecting the brake cylinder with atmosphere, registering openings ineach of the valves for making a pressure connection to the brakecylinder ,'hen the two openings are in registration, pneumaticallyoperated means for moving the second valve to closed position when theair in the brake cylinder is at the predetermined pressure and aresilient electro-magnetically operated means for moving second valve toregistration with the first valve to admit air pressure to the Ilcralrecylinder above the predetermined pressure.

8. In a railway brake mechanism having an air reservoir and brakecylinder on a car, a valve, electro-magnetically operated means foroperating the valve, a second valve, means in the first valve forconnecting the brake cylinder with the atmosphere, registrable openingsin each of the valves for making a pressure connection to the brakecylinder from the air reservoir when the two openings are inregistration, a pneumatically operated piston connected to the brakecylinder for moving the second valve out of registration with the firstvalve to close the pressure connection from the air reservoir to thebrake cylinder when the air in the brake cylinder reaches apredetermined pressure an operator-controlled electro-magnetic powerdevice including a resilient connection in position to exert a force tomove the second valve to re-establish said pressure connection, thusincreasing said predetermined pressure.

9. In a railway brake mechanism having an air reservoir and brakecylinder on a car, a valve, electro-magnetically operated means foroperating the valve, a second valve, means in the rst valve forconnecting the brake cylinder with the atmosphere, openings in each ofthe valves and in position, when properly set, to make a connection fromthe reservoir to the brake cylinder, a pneumatcally operated springpressed piston pneumatically connected to the brake cylinder for movingthe second valve out of registration to close the pressure connectionfrom the reser- Voir to the brake cylinder when the air in the brakecylinder reaches a predetermined pressure an operator-controlledelectro-magnetic power device including a resilient connection inposition to exert a force to move the second valve to re-establish saidpressure connection, thus increasing said predetermined pressure.

10. In a railway brake mechanism having an air reservoir and brakecylinder on a car, a valve, electro-magnetically operated means foroperating the valve, a second valve, means in the first valve forconnecting the brake cylinder with the atmosphere, openings in each ofthe valves and in position, when properly set, to make a connection fromthe reservoir to the brake cylinder, a pneumatically operated piston formoving the second valve out or registration to close the pressureconnection from the reservoir to the brake cylinder when the air in thebrake cylinder reaches a predetermined pressure and springopposedelectro-pneumatically operated means for opening the second valve toincrease the pressure in the brake cylinder.

11. In a railway brake mechanism having an air reservoir and brakecylinder on a car, a valve, electro-magnetically operated means foroperating the valve, a, second valve, means in the first valve forconnecting the brake cylinder with the atmosphere, openings in each ofthe valves and in position, when properly set, to make a connection fromthe reservoir to the brake cylinder, a pneumatically operated piston formoving the second valve out of registration to close the pressureconnection from the reservoir t0 the brake cylinder when the air in thebrake cylinder reaches a predetermined pressure, and anelectromagnetically controlled means for opening the second valve toincrease the pressure.

12. In a railway brake mechanism having an air reservoir and brakecylinder on a car, a valve, electro-magnetically operated means foroperating the valve, a second valve, means in the rst valve forconnecting the brake cylinder with the atmosphere, openings in each ofthe Valves and in position, when properly set, to make a oonnection fromthe reservoir to the brake cylinder, a pneumatically operated piston formoving the second valve out of registration to close the pressureconnection from the reservoir to the brake cylinder when the air in thebrake cylinder reaches a predetermined pressure, an electromagneticallycontrolled means for opening the second valve to increase the pressure,the last named electro-magnetically controlled means including aresilient connection to the second valve.

13. In a railway brake mechanism having an air reservoir and brakecylinder on a car, a valve, electro-magnetically operated means foroperating the valve, a second valve, means in the rst valve forconnecting the brake cylinder with the atmosphere, openings in each ofthe valves and in position, when properly set, to make a connection fromthe reservoir to the brake cylinder, a pneumatically operated piston formoving the second valve, a resilient means tending to oppose themovement of the piston when acted upon pneumatically andelectro-magnetically controlled means, including a resilient member formoving the second Valve to open position to increase the brake cylinderpressure.

14. In a railway brake mechanism having an air reservoir and brakecylinder on a, car, a valve chamber and a valve therein, anelectro-magnet, an armature connected to the valve and in position to beattracted by the magnet, a spring opposing the electro-magnetic actionon the armature, an atmospheric passage, an air passage from thereservoir to the valve chamber, and a passage from the chamber to thebrake cylinder, the valve having a space for and in position to providea connection between the brake cylinder and atmospheric passages whenthe Valve is in one position and an opening in the valve forregistration with the brake cylinder when in another position, a secondvalve and a pneumatic piston having a, cylinder space connected with thebrake cylinder passage, the second valve having an opening forregistration with the opening in the rst valve when the latter isconnected to the brake cylinder passage.

l5. In a railway brake mechanism having an air reservoir and brakecylinder on a car, a valve chamber and a valve therein, anelectro-magnet, an armature connected to the valve and in position to beattracted by the magnet, a spring opposing the electro-magnetic actionon the armature, an atmospheric passage, an air passage from thereservoir to the valve chamber, and a passage from the chamber to thebrake cylinder, the valve having a space for and in position to providea connection between the brake cylinder and atmospheric passages whenthe valve is in one position and an opening in the valve forregistration with the brake cylinder when in another position, a secondvalve, a pneumatic piston having a cylinder space connected with thebrake cylinder passage, the second valve having an opening forregistration with the opening in the rst valve when the latter isconnected to the brake cylinder passage and electro-magnetic means foropposing pneumatic action of the piston.

16. In a railway brake mechanism having an air reservoir and brakecylinder on a oar, a, valve chamber and a valve therein, anelectro-magnet, an armature connected to the valve and in position to beattracted by the magnet, a spring op- 16 posing the electro-magneticaction on the armature, an atmospheric passage, an air passage from thereservoir to the valve chamber, and a passage from the chamber to thebrake cylinder, the valve having a space for and in position to providea connection between the brake cylinder and atmospheric passages whenthe valve is in one position and an opening in the valve forregistration With the brake cylinder when in another position, a secondvalve, a pneumatic piston having a cylinder space connected with thebrake cylinder passage, the second valve having an opening forregistration with the opening in the first valve when the latter isconnected to the brake cylinder passage, an electro-magnetic means, anarmature in position to be operated thereby and resilient means betweenthe pneumatic and the armature.

17. In a railway brake mechanism having an air reservoir and brakecylinder on a car, a valve chamber and a valve therein, anelectro-magnet, an armature connected to the valve and in position to beattracted by the magnet, a spring opposing the electro-magnetic actionon the armature, an atmospheric passage, an air passage from thereservoir to the valve chamber, and a passage from the chamber to thebrake cylinder, the valve having a space for and in position to providea connection between the brake cylinder and atmospheric passages whenthe valve is in one position and an opening in the valve forregistration with the brake cylinder when in another position, a secondvalve, a pneumatic piston having a cylinder space connected with thevbrake cylinder passage, the second valve having an opening forregistration with the opening in the first valve when the latter isconnected to the brake cylinder passage, a resilient member tending tooppose the movement of the pneumatic piston, an electro-magnetic means,an armature in position to be operated thereby and a resilient meansbetween the pneumatic and the armature.

18. In combination, a pneumatic brake mechanism comprising a reservoir,a brake cylinder and means for making a brake application at apredetermined relatively low pressure and an application to the brakesat a relatively higher pressure and including a single pneumaticconnection between the brake cylinder and reservoir, anelectro-magnetically controlled pneumatic valve means in the connectionfor delivering a relatively low predetermined pressure to the brakecylinder, a second electro-magnetic valveaction modifying means for thevalve means for exerting a controlling action thereon and for deliveringa pressure to the brake cylinder greater than the predeterminedpressure.

19. In combination, a pneumatic brake mechanism comprising a reservoir,a brake cylinder and means for making a brake application at apredetermined relatively low pressure and an application to the brakesat a relatively higher pressure and including a pneumatic connectionbetween the brake cylinder and reservoir, an electro-magneticallycontrolled pneumatic valve means in the connection for delivering arelatively low predetermined pressure to the brake cylinder, a secondelectro-magnetic valve-action modifying means for the valve means forexerting a modifying action thereon and for delivering a pressure to thebrake cylinder greater than the predetermined pressure, the valve meansand action modifying means coacting with and in contact with each otherto produce a brake 17 pressure at any point between the predeterminedpressure and the greater pressure.

20. In a railway brake mechanism, having an air reservoir and a brakecylinder on a car, a valve, a second valve, pneumatically controlledmeansl for perating the second valve to coact with the iirst valve toplace the brake cylinder under predetermined air pressure less than thepressure of the air reservoir, an electro-magnetically controlled meansfor operating the rst valve and a second electro-magnetic means foroperating on the pneumatic means to increase the pressure in the brakecylinder above the predetermined pressure.

21. In a multiple-unit train brake system having an air pressure lineextending to a plurality of units of the train and an air pressurereservoir and brake cylinder means on each unit connected to thepressure line, an electrical multiple-control means on one of the trainunits, an electromagnetic means, a pneumatic means, valve meansinterdependently controlled by the electro-magnetic means and pneumaticmeans to establish a predetermined pressure connection between thereservoir and brake cylinder, independently of the air pressure line,and a second electro-magnetic means coacting with the pneumatic meansfor increasing the pressure in the brake cylinder when bothelectro-magnetic means are in simultaneous operation.

22. In a railway brake mechanism having an air reservoir and a brakecylinder on a car, an air pressure passage from the reservoir to thebrake cylinder, a valve and a coacting port in the passage in positionto cut off or admit ow 18 of air under pressure through the passage,elec' tro-magnetically operated means for operating the valve to a uidsupply position, a second valve and a coacting port in the passage forcontrolling the passage of air to the brake cylinder when the firstnamed valve is in fluid supply position, pneumatic means for operatingthe second valve under influence of the brake cyl inder pressure to movethe second valve to a closed-port position when the brake cylinderattains a predetermined pressure, and operatorcontrolledelectro-magnetic power means independent of the rst valve and inposition to move the second valve to, at will, re-establish saidconnection, thus increasing said predetermined pressure.

FRANK S. SWICKARD.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS

